The invention relates to a 4-phase combustion engine equipped with a rotary piston, mainly meant to function as a gasoline using engine. The embodiment of the engine consists of a main cylinder body, in which there is a rotating piston rotor comprising a piston attached to a cylindrical body having a fixed shaft in the middle. Thus the shaft functions as the driving shaft of the engine. The engine is operated by two valves, which either open or close the room existing between the engine body and the piston body. The rotation of the piston is achieved when the gas mixture compressed into explosion volume is closed in between both the valves in such a way that also the piston stays in between the valves. When the piston moves towards the valve in front, it pushes the combustion gas from the front side of the piston to its back side through a groove located in the surface of the main cylinder. When the combustion gas has moved to the back side of the piston, the explosion takes place and the valve in front of the piston opens. Simultaneously the piston closes the combustion chamber. This is followed by the working phase in which the maximal torque of the piston around the shaft improves the motor efficiency by about 65% compared to the present Otto-motor. Correspondingly the fuel consumption and pollution gases decrease about 40%.
Practically almost all present car engines are Otto-motors, in which the rotating motion is achieved by means of a crank shaft. However the use of a crank shaft decreases motor efficiency to a great extent. This results from the fact that when the piston is at its top position and the explosion pressure is at its highest, the length of the torque arm is zero and thus the torque of the motor is zero, too. The torque arm reaches its maximum value when the crank shaft has turned almost 90xc2x0 from its top position. At this stage the explosion pressure has however decreased and is only about ⅕ of the highest pressure. Consequently a great deal of the explosion energy is lost as heat which causes a considerable decrease in motor efficiency.
Nowadays only small quantities of so called Wankel-motors are manufactured. These motors do not have a crank shaft. The operation of the motor is based on the rotation of a triangular piston in an eccentric motion, where the piston pushes the combustion gas forward to a combustion chamber formed by the former piston. In this motor the main defects of a crank shaft have been eliminated, but the eccentric motion has raised new problems: the motors suffer from sealing problems and they break easily. Due to this these motors are currently mainly manufactured for test use.
U.S. Pat. No. 3,692,002 presents a triangular piston structure revolving inside a cylinder. The piston of this motor does not carry out the compression phase, but it is carried out by a compressor outside the motor. Due to the symmetric structure of the motor its torque approaches value zero when the piston approaches the exhaust phase, which decreases the motor efficiency compared to the invention.
U.S. Pat. No. 3,745,979 presents a triangular piston structure, where the pistons move radially inside an elliptical cylinder, where the piston pushes the gas ahead into a storage tank closed by valves. From the storage tank the gas expands to the explosion chamber formed by the former piston. The volume of the explosion chamber increases while combustion gas is led into it. In this structure the pressure in the combustion chamber is smaller than in the storage tank, which decreases the motor efficiency compared to the invention.
Patent publication DE 3926061 A1 presents a motor body and rotor structure similar to the invention but with a different operation. The motor consists of two pairs of pistons, which function by means of eight valves each in turn in such a way that when one pair of pistons is rotating the other one is standing still. According to this functioning principle it is very difficult to construct a functional motor and thus a detailed structure of the motor has not been presented.
According to the invention a so called main cylinder has been made into the engine body and its both ends have been closed by planes forming end walls. Inside the main cylinder there is a revolving piston fastened to a cylindrical piston body, which has a fixed shaft in the middle, which thus functions as a driving shaft of the engine. The engine is operated by two valves. The valves are located in cylinders crossing the main cylinder in such a way that the outer surface of the valves either combines with the cylinder surface of the main cylinder or the valves close the room existing between the engine body and the piston body. The rotating motion of the piston inside the main cylinder is achieved when first the combustion gases compressed into the explosion volume are closed into the room existing between the closed valves in such a way that also the piston remains between the valves. After this the combustion gases are moved from the front side of the piston to its back side through a groove which is wider than the piston in the direction of the cylinder circumference and which is made into the surface of the main cylinder where the explosion chamber is located. While the piston is approaching the valve ahead, it pushes the combustion gases through the groove to the back side of the piston. A little before the piston touches the valve ahead the explosion takes place and the valve opens. At this stage the front edge of the piston has passed over the groove and it touches the surface of the main cylinder thus closing the combustion chamber. This is followed by the working phase of the engine in which the piston revolves in the main cylinder about 290xc2x0.
In addition to the former there is a so called pressure adjustment piston in the engine body at the combustion chamber, which can be used for adjustment of pressure variations, caused by the valves and the piston, while they move in the combustion chamber. This is done in such a way that the pressure adjustment piston decreases the combustion volume at least with the same amount and at the same time that the motion of the piston and the valves increase the combustion volume. This prevents the energy loss, which the decrease of explosion pressure would otherwise cause. Due to the rotation of the piston, it creates a torque which is always at the maximum during the whole working phase. Consequently the motor efficiency is about 65% higher than in conventional crank shaft engines. In addition to the former the invention has features, which are presented in patent claim 1.